[Boatanchors] Boatanchor Sighting in James Bond Movie - Dr. No

[Jim Wiley]

Not so.  The command destruct transmitters were definitely not in the 
VHF range, they were on UHF.  While I remember the specific frequency, I 
am not going to reveal it here, as it may still be in use.  Let's just 
say it was somewhere in the low UHF range.  I also worked at VTS 
(Vandenberg Tracking Station) for a number of years in the mid to late 
60's.  We did indeed use the 200-300 MHz range for satellite downlinks.  
All command uplinks from VTS were either in the 400 MHz range or the 
2200 MHz range.  There was no VHF command capability - or at least none 
that I ever saw - and I worked all over VTS.   The destruct transmitters 
were not at the same site as the satellite downlink station.


The destruct transmitters used an exciter made, I think, by Bendix 
corporation, and the 10 KW amplifiers were manufactured by Collins.  
They were an adaptation of the 10 KW amplifiers used for tropospheric 
scatter links in other locations.  Each destruct site had 2 exciters and 
2 amplifiers that could be used in any combination.  An interesting 
feature was the way the protection circuits were arranged.  If a fault 
occurred in whatever combo was "on line", the other set would be 
switched from hot standby to on-line instantly.  When that happened, the 
remaining setup was put into a mode called "battleshort".  That meant 
that all protective features except for the primary power circuit 
breakers were disabled - that thing wasn't coming off the air unless it 
physically blew apart.  The ultimate expression of the idea that those 
transmissions were so important that the equipment  would be sacrificed 
to the mission, if necessary.


The output from the 10 KW was via 3-5/8" (?)  hardline.   They had some 
"coax relays" built from air-line components that used compressed air to 
blow a "bullet"  center conductor section from one side of   a modified 
"tee" fitting to the other  when switching  between transmitters.  
Noisy, and easily damaged if  accidentally "hot switched" - but they did 
work.  The switchover took less than 50 milliseconds.  Much better than 
having to manually switch "hairpin" links as I had to do on the White 
Alice system (that used similar transmitters and power levels). 


One time, a obsolete missile was launched as a target for the Navy guys 
at Point Mugu NAS.  I think it was a "Bomarc", but it could have been a 
"Snark".  In any case, the Navy managed to blow a part off the target, 
but didn't knock it down.  It just yawed a bit to the left and headed 
for downtown Los Angeles.   They tried to destroy it, but it didn't 
respond - just kept going.   The range safety officer tried the 
Vandenberg site (twice), then the Vandenberg alternate transmitter (also 
twice). then the Pt. Arguello site (also twice for both primary and 
secondary transmitters) with no results, then the Sunnyvale site, then 
the (Channel islands?) site (also twice, then back to Vandenberg to go 
around the ring once again.  They managed to cycle all 8 sets of gear 
two complete times with no effect, then it finally blew on the 3rd 
attempt from Vandenberg main.   There were some nervous controllers 
there for a bit.


Now you want to remember that we're talking 10 KW into an antenna having 
at least 16 dB gain (400 KW ERP)  - and the destruct receivers were not 
just crystal sets!   They were reasonably sensitive receivers - with 
performance in the 1 microvolt range for positive operation. It is 
possible that the first shots at the drone blew off the antenna, or 
destroyed the cable connecting the antenna and the destruct package 
receiver, or perhaps damaged the receiver by detuning it somehow.  No 
one ever mentioned for sure the reason for the problems - at least not 
that I ever heard about.


Working at the command destruct sites was  at least as interesting as 
working at the tracking station,  even if the tracking station job had 
it's moments too.  Much of our gear was "serial number one", so I got so 
see some of what was then considered "state of the art".  Very 
interesting. Some of the data recovery was so hush-hush that an armed 
sentry stood by as the downlink tapes were running, then as soon as a 
"pass" was finished, took the tapes off the machine and went somewhere 
with them.  I never did find out where , but I think it was via military 
jet to Sunnyvale.  I assume they didn't trust the security of our cable 
and microwave links with the sensitive data.


I was born in Lompoc (right next to Vandenberg) and grew up in Santa 
Maria (about 12 miles away).   Got to see so many launches it became 
routine - almost.  I never tired of  running outside to watch a launch.  
Saw quite a few blow up, too.  Better than the Fourth of July.  Bigger, 
anyway.  Worked at VTS (Lockheed) for about 4 years, then at the CDT 
sites (Federal Electric) for about 2 years before coming up to Alaska to 
re-join the White Alice commo system, also working for Federal 
Electric.   I had previously worked for White Alice (then managed by 
RCA) in 1964-1965.  Lots of tubes in those days.


- Jim, KL7CC


J Forster wrote:
> These sites must have been general purpose Command sites, not just
> destruct sites. Launches from VAFB were to the south and south-west...
> nowhere near Sunnyvale.
>
> In those days, commands were transmitted  in the 215 - 260 MHz band,
> later changed to the 2200 - 2290 MHz band. The tri-helix was for the 215
> MHz stuff, the dish for the S band SGLS stuff.
>
> ==============
>
> Jim Wiley wrote:
>
>   
>> Well now, here is something I can really speak about.  I was a
>> technician at the Vandenberg CDT (Command Destruct Transmitter) site
>> during the late 60's and early 70's.  There were at least 4 separate
>> sites that I knew of at that time,  2 were on or near Vandenberg (one
>> was actually at Point Arguello, a naval base next to Vandenberg), one
>> was at or near to Sunnyvale, CA (near San Francisco) and one was
>> somewhere to the South, but I have forgotten where.
>>
>>
>> At our sites, the transmitters were based on a 50-watt class exciter
>> followed by a 10 KW klystron amplifier, feeding either a small dish
>> (about 24 feet) or a tri-helix array.  There were two exciters and two
>> amplifiers at each site, which could be used on any combination.
>> Coaxial relays were used to switch components in and out as needed.
>>
>>
>> More later - I have to run to a meeting.
>>
>>
>> - Jim, KL7CC
>>     
>
>
>
>   
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